Answer:
The Easter Island once used to be extremely diverse in biodiversity. It had abundant amount of plant and animal species living there.
Biodiversity in the past was extremely high due to favorable conditions there. The temperature and climate of Island was favorable for the growth of plants and animals.
It has mild climate with fertile soil which favored growth but now the scenario is different as it is now barren land with lots of sand and no diversity among plants and animal species is found there.